What happened to the CPU frequency in Windows 10?

Question

Windows

In the task manager, in idle, the processor frequency may drop below 1 GHz, and rise to 4.6 under load.

spoiler

Answer 1

This works to save power.
This is fine.
When there is no load, the processor lowers the operating frequencies, consumes less electricity and heats up less. Under load, the frequencies increase.

Answer 2

In the power options, in the current scheme, set the minimum value of the processor.
It defaults to 5%. You can put any.
If performance is more important than energy saving, set to 100% and the processor will always operate at the nominal frequency.
For some applications this is very critical.